ut3_unstack
===========

.. py:function:: t3toolbox.backend.ut3_operations.ut3_unstack(x)

   .. code-block:: python

      def ut3_unstack(
              x: typ.Tuple[
                  NDArray,                          # tucker_supercore
                  NDArray,                          # tt_supercore
                  typ.Tuple[int, ...],              # shape
                  typ.Tuple[NDArray, NDArray],      # (tucker_edge_mask, tt_edge_mask)
              ],
      ):  # -> nested tuple (shaped like stack_shape) of unstacked uniform-T3 .data leaves


   Unstack a uniform Tucker tensor train into an array-like tree of unstacked ones.

   The stack lives at axes ``1 .. len(stack_shape)`` (axis 0 is the mode index ``d``). The supercores
   and the rank masks unstack along it; ``shape`` is shared and replicated onto every leaf (the
   ndarray-only ``(tk, tt, tkm, ttm)`` go through the tree machinery; ``shape`` is woven in after).